They get your login info for eBay from you, then their servers have a program that logs the bid right before the auction ends. I've used it a couple times from sites offering free trials - they all seem to work about the same. Just make sure you're using a reputable one, since you are, after all, giving away your login information for eBay.

Just a word of warning! If ebay finds out that you are using such a service they will suspend permanently your account.

That's not my understanding. In fact I found this when I googled it:

"Q. Is sniping illegal, against eBay policy, fraud, or dishonest?

A. No. Sniping is 100% allowed according to eBay policy. eBay's help center found here, lists sniping as one of the few complaints they specifically will not investigate. Section 7 of eBay's privacy policy found here, states that you can share your password with a third party if you choose to."

This is the actual eBay policy on sniping, copied from their page here:

"What we won’t investigate

Someone outbid me at the last minute. Placing a high bid in the closing seconds of an auction-style listing is called “sniping” within the eBay community. Sniping is part of the eBay experience, and all bids placed before a listing ends are valid, even if they're placed one second before the listing ends. Learn how to avoid being outbid."

And this is the part of their policy about password-sharing:

"Your password is the key to your account. Use unique numbers, letters and special characters, and do not disclose your eBay password to anyone. If you do share your password or your personal information with others, remember that you are responsible for all actions taken in the name of your account."

Last edited by dalecooper on Fri Jan 09, 2009 10:30 am; edited 1 time in total

why would you give some random site ypur personal ebay details , your just asking for trouble. If your gonna snipe do it in person.

For auctions that end in the middle of the night, or when I'm going to be out of town or something. I've sniped a couple dozen auctions myself, but I've had to use sites for a few others because of when they were ending.

If something is so damned important put your bid in at $666 day one and probably win everything as well._________________Bloodline Ascension Temple : https://soundcloud.com/bloodlineascensiontemple
...and so sayeth the Yosuke to Demoniarch ...troll as ye please, for thy IXTAB will turn the blind eye upon thee!!!
Yosuke and IXTAB are my friends. (best friends)

If something is so damned important put your bid in at $666 day one and probably win everything as well.

That'll just drive up the price needlessly though. Why pay more if you don't have to?

The selling of items way higher than their real value is the whole bread and butter of bidding and what ebay is designed for. This is what bidding does.
This sniping just raises the final price as well higher than it needs to be, every bid does no matter how the bid is made.
Anything requiring a bid to win is fishing for a price higher than the value of the item is actually worth, otherwise everything would list as buy it now's._________________Bloodline Ascension Temple : https://soundcloud.com/bloodlineascensiontemple
...and so sayeth the Yosuke to Demoniarch ...troll as ye please, for thy IXTAB will turn the blind eye upon thee!!!
Yosuke and IXTAB are my friends. (best friends)

The selling of items way higher than their real value is the whole bread and butter of bidding and what ebay is designed for. This is what bidding does.
This sniping just raises the final price as well higher than it needs to be, every bid does no matter how the bid is made.
Anything requiring a bid to win is fishing for a price higher than the value of the item is actually worth, otherwise everything would list as buy it now's.

WITHIN THE STRUCTURE OF THE BIDDING SYSTEM, sniping is a proven method to reduce the final price. Here's a standard eBay auction scenario: rare item X is bid on by user A for a maximum price of $20. User B comes along and bids $25 and is the new high bidder at 21. User A stews over it, decides he can afford a little more, and ups his bid to 30 - now he's leading at 26. User B comes back and ups his bid to 35, taking over again at a price of 31. User A decides he's had enough and bows out. Item sells for 31.

The exact same auction - if user B had just sniped at the very end, he would have won the thing for 21.00 instead of 31.00. He saves 10.00.

It's not always that clear-cut of course, and if all participants try to snipe you still end up paying close to the same price you would have in a regular bidding war. And of course, if everyone just bid the most they were willing to pay, with no compromise or re-bidding later on, sniping would be pointless. But the fact is, buyers always change their minds when they see they've been outbid by $1 - they decide they can afford just a little bit more. Sniping avoids further price inflation by cutting down on the cycles of people adjusting to being outbid and changing their idea of the item's worth to them.